George thompson



uiten' aient time.

GEORGE THOMPSON, OF NASHUA, NEW HAMPSHIRE.

Letters Patent No. 81,434, elated August 25, 1868.

IMPROVEMENT IN BELT-SAWS.

TO-ALL WI-IOM IT MAY CONOERN:

Be it known that I, GEORGE THOMPSON, of Nashua, in the county of Hillsboro, and State of New Hamp s hire, have invented a new and usefullmprovement in `Operating Belt-Saws; and I do hereby declare that thi Following is a full, clear, and exact description thereof, which ,will enable others skilled in the art to maire au( use the same, reference being had' to the accompanying drawings, forming part of this speeilieation, in which- Figure 1 is a side view of my invention.

Figure 2 is a detail top view ofthe table.

Similar letters of reference indicate like parts.

The objectief this invention is to provide a means of operating` belt-saws, whereby the curve of the saw, a the peint of its operation on the wood, may bc varied to cut staves, lagging, (so eallefh) and other work of 1 curved character, for which it may be applicable. i

Itconsists of a belt-sawsteadied by a number of adjustable small pulleys, and ruiming on a main pulley which is driven by a driving-belt which is so arranged upon several otherpulleys as to hug the main driving pulley for halt of its circumference, and by its friction against the same transmit motion to it.

In the accompanying drawings the main driving-pulley is shown at A. The saw als an ordinary belt-sai of ilexible quality running on the pulley A, as shown, and held in a suitable curve by the rollers or small pu` leys d d d, Ste., of any suitable number, some of the said small pulleys being within and some without the sar assbown, for the purpose of "holding the part et' the saw which is not in contact with thepulley A in the desire curve, suitable for sawing timber with the desired curve.

The small p`ulleys-are adjustable toand fro by means of the blocks f, which bear the bosses or studs e., o which the said pulleys revolve, the studs e being provided with set-nuts, which, when screwed up, impinge again: the back of the plate D, iny whichthe slots are made, thus holding the small pulleys firmly iixed in the desire vposition 'for maintaining the cutting part of the saw in requisite curve. Y

The driving-belt Ois made-to hug the pulley A by the three pulleysB B B, arranged in such correlation l `the pulley A, as to cause the belt lto lie or bug against the said pulley, and thus drive it and the saw. Th belt also embraces the saw upon the pulley A, and holds it firmly to the same, as shown.

The saw-table H is provided with a curved carriage, G, which slides'in a. correspondingly-curved groove the table,'thus serving as a feed-board to guide the wood'being sawed in the proper curved direction as it is fc up to the saw, thus,v enabling stares or other curved forms to be s awed with regularity. l

The bosses or studs of'the pulleys AB B B may be alxed to the plate D, or in any other suitable arrang ment orframe.

The feed-table may be variously modified, nothing being claimed in the particular construction shown.

The'actuating-powers may be transmitted to the pulley A, or to that oi' any one of the pulleys B B.

Havingthus described my invention, I claim as new, and desire to secure by'Letters Patent- The arrangement, substantially as herein shown and describechof the pulleys d, each adjustable indcpen ently of the others, with relation to the pulley A and saw a, as set forth.

GEORGE THOMPSON.

,'Witnesscs HENRY A. SPorFonD, 4SMITH G. Mooney. 

